In recent years, personal navigation systems capable of pedestrian-centric route guidance have been widely equipped in portable terminals, such as cellular phones, smart phones, PDAs and MP3 players. The personal navigation system refers to a system that detects the location of a pedestrian to be guided by the system and guides a route for the pedestrian by using the detected location of the pedestrian.
A personal navigation system for pedestrian navigation may be implemented by equipping a portable terminal with a GPS receiver, an accelerometer, a gyroscope, and such. This personal navigation system estimates the step length of a pedestrian and produces a navigation solution by using the estimated step length to thereby provide a navigation service. Thus, in order to provide an accurate navigation service, the step length of a pedestrian should be accurately measured.
In the prior art, the step length of a pedestrian is estimated without considering in which body part the pedestrian carries a portable terminal during his/her movement. In the process of estimating the step length in this manner, a considerable error may occur depending on the position of the portable terminal carried by the pedestrian in different body parts which, in the worst case scenario, may result in a large deterioration in step length estimation performance.